1. Field of the Invention
The present invention relates to an in-plane switching (IPS) mode liquid crystal display (LCD) and its fabrication method.
2. Discussion of the Related Art
As users' interest in information displays grows and the demand for portable (mobile) information devices increases, research and commercialization of light thin flat panel displays (FPD), which can replace the CRT (Cathode Ray Tube), the existing display device, are actively ongoing.
Among FPDs, the LCD, a device for displaying images by using optical anisotropy of liquid crystal, exhibits excellent resolution and color and picture quality, so it is commonly used for notebook computers or desktop monitors and the like.
The LCD includes a color filter substrate, an array substrate, and a liquid crystal layer formed between the color filter substrate and the array substrate.
As switching elements of the LCD, generally, thin film transistors (TFTs) are used, and as a channel layer of the TFT, an amorphous silicon thin film is used.
The related art LCD will be described in detail with reference to FIG. 1.
FIG. 1 is an exploded perspective view showing the related art LCD.
As shown in FIG. 1, the LCD includes a color filter substrate 5, an array substrate 10 and a liquid crystal layer 30 formed between the color filter substrate 5 and the array substrate 10.
The color filter substrate 5 includes color filters (C) including a plurality of sub-color filters 7 implementing red, green and blue colors, black matrixes 6 for dividing the sub-color filters 7 and blocking light transmission to the liquid crystal layer 30, and a transparent common electrode 8 for applying voltage to the liquid crystal layer 30.
The array substrate 10 includes a plurality of gate lines 16 and a plurality of data lines 17 arranged horizontally and vertically to define a plurality of pixel regions (P), TFTs, the switching elements, formed at each crossing of the gate lines 16 and data lines 17, and pixel electrodes 18 formed on each pixel region (P).
The color filer substrate 5 and the array substrate 10 face each other and are attached by a sealant (not shown) formed on an outer edge of an image display region to form a liquid crystal display panel, and the two substrates 5 and 10 may be attached by an attachment key (not shown) formed on the color filter substrate 5 or on the array substrate 10.
As a driving method generally used for the LCD, a twisted nematic (TN) method for driving nematic liquid crystal molecules in a direction perpendicular to the substrates is used, which is, however disadvantageous in that its viewing angle is 90 degrees, namely, narrow. This results from refractive anisotropy of the liquid crystal molecules. Namely, when voltage is applied to the liquid crystal panel, the liquid crystal molecules aligned to be horizontal to the substrates are aligned in a direction almost perpendicular to the substrates.